Explosions rocked the Brussels airport and the subway system on Tuesday, only days after the main suspect in the November Paris attacks was arrested in the city, police said. [Geert Vanden Wijngaert/AP]

A policewoman gestures in front of ambulances at the scene of a blast outside a metro station in Brussels. [Reuters]

European Union foreign policy chief Federica Mogherini reacts to news of the Belgium blasts during a joint news conference with Jordanian Foreign Minister Nasser Judeh at the Ministry of Foreign Affairs in Amman. [Muhammad Hamed/Reuters]